红细胞膜外翻囊泡钙摄取方法的建立

Preparation of Inside-out Vesicles from Red Blood Cell Membranes and Measurement for Its Ca2+ Uptake

细胞膜上的ATP和Mg^(2+)依赖性的Ca^(2+),Mg^(2+)-ATP酶(即钙泵)的基本功能是主动转运Ca^(2+),维持胞内Ca^(2+)的相对恒定.细胞内Ca^(2+)浓度持续升高将会危及细胞的各种功能.细胞膜Ca^(2+)转运障碍与高血压发病有密切关系.红细胞膜是研究各种浆膜Ca^(2+)转运的理想模型.作者改进了文献方法.建立了以红细胞膜IOV来研究Ca^(2+)摄取的方法,为研究高血压发病过程中细胞膜Ca^(2+)的摄取异常机理,提供了一种可靠的手段.

Sealed, inside-out red cell membrane vesicles (IOV) from rats were prepared by a modified method of Steck (1974). The preparation contained 70% of IOV. In the presence of ATP and Mg2+, these vesicles actively took up Ca2+ with a high efficiency and reproducibility. The intraassay coefficient of variance (C.V.) was 3.6% and the interassay C.V. was 13.58%. The active Ca2+ transport reached the maximal level in 10 minutes of incubation, and linearly correlated with the IOV concentration. The Ca2+ uptake rate in Wistar rats was 9.39± 1,28nmol/mg IOV protein/min. IOV rapidly lost Ca2+ when A23187 was added. The active transport was stimulated by calmod-ulin, and inhibited by trifluoperazin.